[RFA] Add dwarf4 values to include/dwarf2.h

[RFA] Add dwarf4 values to include/dwarf2.h

[Doug Evans]

Hi.

This patch adds various dwarf4 elements, plus DW_AT_GNU_odr_signature,
to include/dwarf2.h.

Ok to check in?

[I have a gdb patch that's ready to go in to support "comdat types".
And this will also be needed for the gcc side, which is currently
on the dwarf4 branch.]

2009-07-15  Doug Evans  <dje@google.com>
	    Cary Coutant  <ccoutant@google.com>

	* dwarf2.h (enum dwarf_tag): Add DW_TAG_type_unit.
	(enum dwarf_form): Add DW_FORM_sec_offset, DW_FORM_exprloc,
	DW_FORM_flag_present, DW_FORM_sig8.
	(enum dwarf_attribute): Add DW_AT_signature, DW_AT_GNU_odr_signature.

diff -u -p -r1.2 dwarf2.h
--- dwarf2.h	9 Jul 2009 21:01:15 -0000	1.2
+++ dwarf2.h	14 Jul 2009 23:22:35 -0000
@@ -194,6 +194,8 @@ enum dwarf_tag
     DW_TAG_imported_unit = 0x3d,
     DW_TAG_condition = 0x3f,
     DW_TAG_shared_type = 0x40,
+    /* DWARF 4.  */
+    DW_TAG_type_unit = 0x41,
 
     DW_TAG_lo_user = 0x4080,
     DW_TAG_hi_user = 0xffff,
@@ -244,7 +246,12 @@ enum dwarf_form
     DW_FORM_ref4 = 0x13,
     DW_FORM_ref8 = 0x14,
     DW_FORM_ref_udata = 0x15,
-    DW_FORM_indirect = 0x16
+    DW_FORM_indirect = 0x16,
+    /* DWARF 4.  */
+    DW_FORM_sec_offset = 0x17,
+    DW_FORM_exprloc = 0x18,
+    DW_FORM_flag_present = 0x19,
+    DW_FORM_sig8 = 0x20
   };
 
 /* Attribute names and codes.  */
@@ -342,6 +349,8 @@ enum dwarf_attribute
     DW_AT_elemental     = 0x66,
     DW_AT_pure          = 0x67,
     DW_AT_recursive     = 0x68,
+    /* DWARF 4 values.  */
+    DW_AT_signature     = 0x69,
 
     DW_AT_lo_user = 0x2000,	/* Implementation-defined range start.  */
     DW_AT_hi_user = 0x3ff0,	/* Implementation-defined range end.  */
@@ -381,6 +390,7 @@ enum dwarf_attribute
     DW_AT_body_begin = 0x2105,
     DW_AT_body_end   = 0x2106,
     DW_AT_GNU_vector = 0x2107,
+    DW_AT_GNU_odr_signature = 0x210f,
     /* VMS extensions.  */
     DW_AT_VMS_rtnbeg_pd_address = 0x2201,
     /* UPC extension.  */

Re: [RFA] Add dwarf4 values to include/dwarf2.h

[Doug Evans]

On Thu, Jul 16, 2009 at 1:54 PM, Doug Evans<dje@google.com> wrote:
> Hi.
>
> This patch adds various dwarf4 elements, plus DW_AT_GNU_odr_signature,
> to include/dwarf2.h.
>
> Ok to check in?
>
> [I have a gdb patch that's ready to go in to support "comdat types".
> And this will also be needed for the gcc side, which is currently
> on the dwarf4 branch.]
>
> 2009-07-15  Doug Evans  <dje@google.com>
>            Cary Coutant  <ccoutant@google.com>
>
>        * dwarf2.h (enum dwarf_tag): Add DW_TAG_type_unit.
>        (enum dwarf_form): Add DW_FORM_sec_offset, DW_FORM_exprloc,
>        DW_FORM_flag_present, DW_FORM_sig8.
>        (enum dwarf_attribute): Add DW_AT_signature, DW_AT_GNU_odr_signature.
>
> diff -u -p -r1.2 dwarf2.h
> --- dwarf2.h    9 Jul 2009 21:01:15 -0000       1.2
> +++ dwarf2.h    14 Jul 2009 23:22:35 -0000
> @@ -194,6 +194,8 @@ enum dwarf_tag
>     DW_TAG_imported_unit = 0x3d,
>     DW_TAG_condition = 0x3f,
>     DW_TAG_shared_type = 0x40,
> +    /* DWARF 4.  */
> +    DW_TAG_type_unit = 0x41,
>
>     DW_TAG_lo_user = 0x4080,
>     DW_TAG_hi_user = 0xffff,
> @@ -244,7 +246,12 @@ enum dwarf_form
>     DW_FORM_ref4 = 0x13,
>     DW_FORM_ref8 = 0x14,
>     DW_FORM_ref_udata = 0x15,
> -    DW_FORM_indirect = 0x16
> +    DW_FORM_indirect = 0x16,
> +    /* DWARF 4.  */
> +    DW_FORM_sec_offset = 0x17,
> +    DW_FORM_exprloc = 0x18,
> +    DW_FORM_flag_present = 0x19,
> +    DW_FORM_sig8 = 0x20
>   };
>
>  /* Attribute names and codes.  */
> @@ -342,6 +349,8 @@ enum dwarf_attribute
>     DW_AT_elemental     = 0x66,
>     DW_AT_pure          = 0x67,
>     DW_AT_recursive     = 0x68,
> +    /* DWARF 4 values.  */
> +    DW_AT_signature     = 0x69,
>
>     DW_AT_lo_user = 0x2000,    /* Implementation-defined range start.  */
>     DW_AT_hi_user = 0x3ff0,    /* Implementation-defined range end.  */
> @@ -381,6 +390,7 @@ enum dwarf_attribute
>     DW_AT_body_begin = 0x2105,
>     DW_AT_body_end   = 0x2106,
>     DW_AT_GNU_vector = 0x2107,
> +    DW_AT_GNU_odr_signature = 0x210f,
>     /* VMS extensions.  */
>     DW_AT_VMS_rtnbeg_pd_address = 0x2201,
>     /* UPC extension.  */
>
>

Hi.
I checked this into both gcc/binutils trees, without DW_AT_GNU_odr_signature.
[approved by Ian off-list]

Re: [RFA] Add dwarf4 values to include/dwarf2.h

[Ben Elliston]

On Thu, 2009-07-16 at 13:54 -0700, Doug Evans wrote:

> This patch adds various dwarf4 elements, plus DW_AT_GNU_odr_signature,
> to include/dwarf2.h.

Should this file even be called dwarf2.h any more?

Ben

Re: [RFA] Add dwarf4 values to include/dwarf2.h

[Cary Coutant]

>> This patch adds various dwarf4 elements, plus DW_AT_GNU_odr_signature,
>> to include/dwarf2.h.
>
> Should this file even be called dwarf2.h any more?

DWARF-2 was so different from DWARF-1, it was essentially a new
format, so it made sense at the time. DWARF-3 and DWARF-4 are just
mostly-compatible extensions of DWARF-2, and updating the name for
each new revision would only be counterproductive. Just think of it as
"dwarf2+.h".

-cary

Re: [RFA] Add dwarf4 values to include/dwarf2.h

[Tom Tromey]

>>>>> "Doug" == Doug Evans <dje@google.com> writes:

Doug> +    DW_AT_GNU_odr_signature = 0x210f,

I would like to ask that all new GNU extensions be documented in
dwarf2.h.  The existing extensions are already the subject of some
bafflement; I would like to end this practice.

I think my ideal form for this would be a long comment in the style of
the rest of the DWARF standard -- something that someone already
familiar with DWARF could readily read and understand.

Tom

Re: [RFA] Add dwarf4 values to include/dwarf2.h

[Doug Evans]

On Thu, Jul 16, 2009 at 2:15 PM, Tom Tromey<tromey@redhat.com> wrote:
>>>>>> "Doug" == Doug Evans <dje@google.com> writes:
>
> Doug> +    DW_AT_GNU_odr_signature = 0x210f,
>
> I would like to ask that all new GNU extensions be documented in
> dwarf2.h.  The existing extensions are already the subject of some
> bafflement; I would like to end this practice.
>
> I think my ideal form for this would be a long comment in the style of
> the rest of the DWARF standard -- something that someone already
> familiar with DWARF could readily read and understand.

Maybe this patch should be split into two then.